Filtering member for filters

Abstract

A filter assembly for the filtration of a liquid or gaseous substance comprising a frame and a plurality of filter members fitted in the frame in parallel relation to one another. Each filter member consists of two elements connected together to form a hollow interior, the substance to be filtered being introduced at one side of the filter and passing through the hollow interior and then through the filter elements for discharge between adjacent filter elements of adjoining filter memers. Each filter element comprises a layer of fiber glass and at least one fleece layer, the two layers being connected by needle felting together at locations between the connections of the filter elements constituting the filter member.

What is claimed is: 
     
       1. In a high efficiency type filter assembly comprising a pair of opposed substantially coextensive side walls forming major filtering areas, each side wall including a layer of glass fiber and at least one covering layer, said side walls having parallel, longitudinal edges and a transverse edge and being joined together to form at least one bag with an open inlet mouth for entry of the substance to be filtered, said substance passing through the side walls of said at least one bag, the improvement wherein said covering layer consists of a fleece pad disposed on at least one side of said layer of glass fiber, means comprising needle felting joining said covering layer and said layer of glass fiber together in spaced parallel rows in each of said side walls, means comprising a single row of needle felting joining said side walls together and means comprising a plurality of adjacent rows of needle felting extending parallel to said longitudinal edges of the side wall and constituting a fraction of the length thereof to form a seam at said transverse edge. 
     
     
       2. In a high efficiency type filter assembly as claimed in claim 1 wherein a plurality of said single rows of needle felting join said side walls together to form a plurality of parallel extending bags. 
     
     
       3. In a high efficiency type filter assembly as claimed in claim 2 wherein two of said covering layers are disposed on opposite sides of each layer of glass fiber whereby each side wall is composed of three layers of material. 
     
     
       4. In a high efficiency type filter assembly as claimed in claim 3 wherein each covering layer is connected to the layer of glass fiber by parallel rows of said needle felting all three layers of each side wall being connected by needle felting in further parallel rows. 
     
     
       5. In a high efficiency type filter assembly comprising a pair of opposed substantially coextensive side walls forming major filtering areas, each side wall including a layer of glass fiber and a covering layer on opposite surfaces of the layer of glass fiber whereby each side wall is composed of three layers of material, said side walls having parallel longitudinal edges and a transverse edge and being joined together to form at least one bag with an open inlet mouth for entry of the substance to be filtered, said substance passing through the side walls of said at least one bag, the improvement wherein each said covering layer consists of a fleece pad, means comprising needle felting joining said covering layers and said layer of glass fiber together in spaced parallel rows in each of said side walls, means comprising a single row of needle felting joining said side walls together, each covering layer being connected to the associated layer of glass fiber by parallel longitudinal rows of said needle felting, all three layers of each side wall being connected by said needle felting in further parallel longitudinal rows, and a plurality of adjacent, parallel, longitudinal rows of needle felting at said transverse edge extending over a fraction of the length of the longitudinal edges to form a seam at said transverse edge.